org.apache.mahout.math.jet.random

Class Normal

java.lang.Object

org.apache.mahout.math.function.DoubleFunction

org.apache.mahout.math.jet.random.AbstractDistribution

org.apache.mahout.math.jet.random.AbstractContinousDistribution

org.apache.mahout.math.jet.random.Normal

All Implemented Interfaces:

IntFunction

public class Normal
extends AbstractContinousDistribution

Implements a normal distribution specified mean and standard deviation.

Constructor Summary

Constructors

Constructor and Description
Normal(double mean, double standardDeviation, Random randomGenerator)

Method Summary

Methods

Modifier and Type	Method and Description
double	cdf(double x) Returns the cumulative distribution function.
double	nextDouble() Returns a random number from the distribution.
double	pdf(double x) Returns the probability density function.
void	setRandomGenerator(Random randomGenerator) Sets the uniform random generator internally used.
void	setState(double mean, double standardDeviation) Sets the mean and variance.
String	toString() Returns a String representation of the receiver.

Methods inherited from class org.apache.mahout.math.jet.random.AbstractContinousDistribution

nextInt

Methods inherited from class org.apache.mahout.math.jet.random.AbstractDistribution

apply, apply, getRandomGenerator, randomDouble

Methods inherited from class org.apache.mahout.math.function.DoubleFunction

isDensifying

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Normal

public Normal(double mean,
      double standardDeviation,
      Random randomGenerator)

Parameters:

mean - The mean of the resulting distribution.

standardDeviation - The standard deviation of the distribution.

randomGenerator - The random number generator to use. This can be null if you don't need to generate any numbers.

Method Detail

cdf

public double cdf(double x)

Returns the cumulative distribution function.

Overrides:

cdf in class AbstractContinousDistribution

pdf

public double pdf(double x)

Returns the probability density function.

Overrides:

pdf in class AbstractContinousDistribution

nextDouble

public double nextDouble()

Returns a random number from the distribution.

Specified by:

nextDouble in class AbstractDistribution

Returns:

A new sample from this distribution.

setRandomGenerator

public final void setRandomGenerator(Random randomGenerator)

Sets the uniform random generator internally used.

Overrides:

setRandomGenerator in class AbstractDistribution

Parameters:

randomGenerator - the new PRNG

setState

public final void setState(double mean,
            double standardDeviation)

Sets the mean and variance.

Parameters:

mean - The new value for the mean.

standardDeviation - The new value for the standard deviation.

toString

public String toString()

Returns a String representation of the receiver.

Overrides:

toString in class Object